opinions on amp for Totem Mani Sigs

I am powering my Mani's with a Musical Fidelity a5.5 (250 per side into 8 ohms, 400 into 4 ohms). The amp is satisfactory for the most part,but seems a lack a bit of oomph when I listen to high volume R&R. Lots of mani owners suggest Simaudio I-7 integrated and Plinius 9200 but I am now looking at going the separates route. Some recommended amps+ pre which might hit my price point of <$5K:

Sim W-5/P-5 (used)
Bryston 4B SST plus pre

The Plinius SB-300/301 plus pre (may be to too pricey even used)

What about the Pass 250.5 plus X-1 pre? Pass amps appear to pack plenty of juice and look mighty sexy but I haven't seen comments about how Pass matches up synergy-wise with the manis. I am looking to make a major step up if I spring for the extra dough, other wise I will stay put with the MF a5.5. Anyone care to offer an opinion?
I'd love to hear the Manis in my system with the ARC sp16 pre and Bel Canto ref1000m mono blocks.

I run a pair of Dynaudio Contour 1.3mkii monitors, which is not too far removed from what I've heard with Manis, with this combo and I think Mani's would really shine.

I've heard the Dynaudios sound a touch hot in comparison off a Musical FIdelity A3CR amp I had prior, and same with the Mani's at a dealer running off newer, larger McIntosh SS amplification.

Class D amps with quality power supplies like the Bel Cantos in general are a good match I would bet in that they are powerful with little or no fatigue factor with most everything I have tried them with. A good well matched tube pre-amp doesn't hurt either.
I'm not familiar with any of the amps you mention, but I drive my manis with monoblocks/preamp - the amps are rated at 400 w @ 4 ohms, and do just fine. I find it peculiar that your MF amp leaves you wanting unless it's simply much over rated on output.
I think that my Musical Fidelity amp may be taxed by the low impedance curve of the mani-2's. They are said to go as low as 2 ohms and I am not sure that the MF amp can deliver the required current

I wouldn't say the MF can't do it, but I suspect that other amps can do it better. Few integrateds are champs at delivering lots of current. Separates are generally able to do it better and more cost effectively.

I think current delivery matters a lot with the mani's. You want an amp that is a champ at delivering current into low impedance for best results with those.
a few of the McCormack amps like they might be up to the challenge too plus at a good price used(DNA-2, DNA-225 and DNA 500). Not as sexy looking as the Pass amps with the big blue meter, but stable down to 1 ohm with high current.